Interesting... I can add notes, but I cannot select note properties, and I cannot draw velocities...
And when I add notes, it adds them to a new clip, not the existing clip.
And if I double-click on a different clip, I can select and change notes just fine...
So it seems like the clip I've been trying to edit is "locked", or there is an invisible clip sitting on top of it.
...and guess what, if I then click on the "locked" clip, it's no longer locked, and I can edit it.
I then exit Sonar, and can repeat it. At first, the clip is uneditable. If I then select a different clip, and then come back to the first clip, it's editable again.
Very odd!